Typically, aquariums contain fish or other aquatic organisms, water, various organic materials, and multiple types of bacteria. One type of bacteria “feeds” on organic materials, such as the fecal matter of fish, fish food, portions of aquatic plants, etc. Some bacteria consumes organic materials partially and leaves behind the remainder to rot and foul the water by way of cloudiness, elevated toxins and a rancid smell. Resulting elevated nitrates, nitrites and ammonia, in sufficient concentration in the aquarium water, can kill fish and other aquatic organisms.
Another type of bacteria commonly present in aquariums feeds on ammonia, reducing the potentially toxic ammonia concentration in the aquarium water. However, the first harmful type of bacteria can multiply very rapidly, especially when excess organic material is introduced into the aquarium water. Such excess can occur through excess feeding of the fish, the death of a fish or aquatic plant, or the addition of fish to the aquarium. As a result, the harmful bacteria may reproduce rapidly, producing ammonia at a rate much greater than the beneficial bacteria consume the ammonia. When the ammonia reaches a sufficient concentration, a large number of expensive fish may rapidly die. In order to avoid this cycle, introduction of new fish into an aquarium is often done one at a time, over a protracted time period, so that a balance between the ammonia producing bacteria and the ammonia consuming bacteria can be maintained.
In addition to the ammonia produced by the action of bacteria on organic matter, fish urine is an additional source of ammonia. Conventional activated charcoal water filters have been employed to reduce the ammonia concentration, but these filters are expensive and must be frequently changed and maintained.
Other types of bacteria found in aquarium water can produce disease in both fish and humans. Individuals who work in the field of aquarium services and cleaning are particularly susceptible to such diseases.
If reproduction of bacteria is inhibited, then decay of organic matter will be slowed, reducing the spread of disease, cloudiness of the water will be minimized, and a relatively small number of ammonia consuming bacteria will still be adequate to prevent the ammonia, nitrates and nitrites from reaching a toxic concentration.